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Abdel-Shafi S, Abd El-Hack ME, Amen S, Helmi A, Swelum AA, Tellez-Isaias G, Enan G. The efficacy of some probiotics and prebiotics on the prevalence of E. coli and the immune response of chickens. Poult Sci 2023; 102:103219. [PMID: 37993387 PMCID: PMC10755822 DOI: 10.1016/j.psj.2023.103219] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/14/2023] [Accepted: 10/17/2023] [Indexed: 11/24/2023] Open
Abstract
The present study aimed to investigate the efficacy of probiotics and prebiotics in controlling Escherichia coli (E. coli) spp. isolated from chicken. A total of 230 birds representing 19 different commercial breeds were taken from various points. Birds were monitored for postmortem and clinical investigation. Aseptically collected liver samples, lungs, kidneys, hearts, and yolk sacs were then subjected to bacterial isolation and identification. E. coli were observed in 9 pooled samples from 120 examined with an incidence of 7.5%. Nine farms were E. coli-positive, with an incidence of farm infection of 47.3%. The 9 suspected isolates of E. coli were profiled by morphological and microbiological identification of the colony, motility, and gram reaction. The serogroup analysis showed 9 different E. coli for which 3 other groups were identified: 2 E. coli O78, 3 E. coli O111, and 4 untyped groups. Nine isolates of E. coli were subjected to PCR. Molecular detection of 9 strains was conducted to find the virulence genes of E. coli strains (8 STX1, 4 STX2, and 9 EAE). Probiotics and prebiotics significantly increased the total erythrocytic and leukocytic counts throughout the experiment. The phagocytic percentage's main values at 14 d were 47 and 30%, respectively. An increase in the humoral immunity against Newcastle disease (ND) was noticed after ND vaccination. The geometric mean (HI) was 5.9 and 4.2 for probiotic and prebiotic, respectively. It could be concluded that probiotics and prebiotics could stimulate a nonspecific immune response against experimental infection with a virulent strain of E. coli spp.
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Affiliation(s)
- Seham Abdel-Shafi
- Botany and Microbiology Department, Faculty of Science, Zagazig University, Zagazig 44511, Egypt
| | - Mohamed E Abd El-Hack
- Poultry Department, Faculty of Agriculture, Zagazig University, Zagazig 44511, Egypt
| | - Samy Amen
- Bacteriology Department, Animal Health Research, Zagazig, Egypt
| | - Anaam Helmi
- Botany and Microbiology Department, Faculty of Science, Zagazig University, Zagazig 44511, Egypt
| | - Ayman A Swelum
- Department of Animal Production, College of Food and Agriculture Sciences, King Saud University, Riyadh 11451, Saudi Arabia.
| | | | - Gamal Enan
- Botany and Microbiology Department, Faculty of Science, Zagazig University, Zagazig 44511, Egypt
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2
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Wilczyński J, Stępień-Pyśniak D, Wystalska D, Wernicki A. Molecular and Serological Characteristics of Avian Pathogenic Escherichia coli Isolated from Various Clinical Cases of Poultry Colibacillosis in Poland. Animals (Basel) 2022; 12:1090. [PMID: 35565517 PMCID: PMC9106014 DOI: 10.3390/ani12091090] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/14/2022] [Accepted: 04/21/2022] [Indexed: 11/17/2022] Open
Abstract
Escherichia coli infections are a major problem in modern poultry production. Avian pathogenic E. coli (APEC) strains have several mechanisms that enable them to colonize various ecosystems. In this study, 290 E. coli isolates were recovered from clinical cases of colibacillosis in chicken and turkey broilers and from laying and breeding hens. The samples were taken from organs with pathological changes suggesting colibacillosis. The lesions were assigned to three groups depending on their advancement, of which the largest (60% of the isolates) was group 3, with the most extensive changes. The most common serotype was shown to be O78 (14%). The most frequently detected gene among those tested was iss, while papC was the least prevalent. An analysis of the number of genes present per isolate revealed that the presence of four genes was the most common (22%), while only 1% of the strains tested had all eight genes. The most frequently detected genes for each serotype were iss and iucD for O78; irp2 and cvi/cva for O1; irp2, iucD, and iss for O2, and iss and iucD for O8, for which the least frequent was papC. All O18 serotype strains had the iss gene, while none had the vat gene.
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Affiliation(s)
- Jarosław Wilczyński
- Veterinary Diagnostic Laboratory Lab—Vet, 62-080 Tarnowo Podgórne, Poland; (J.W.); (D.W.)
| | - Dagmara Stępień-Pyśniak
- Department of Veterinary Prevention and Avian Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, 20-612 Lublin, Poland;
| | - Danuta Wystalska
- Veterinary Diagnostic Laboratory Lab—Vet, 62-080 Tarnowo Podgórne, Poland; (J.W.); (D.W.)
| | - Andrzej Wernicki
- Department of Veterinary Prevention and Avian Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, 20-612 Lublin, Poland;
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3
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Liu CW, Wang P, Cao GN, Zou QH. Complete genome sequence and virulence characterization of a neonatal meningitis Escherichia coli isolate. Microb Pathog 2021; 160:105199. [PMID: 34560248 DOI: 10.1016/j.micpath.2021.105199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/13/2021] [Accepted: 09/14/2021] [Indexed: 10/20/2022]
Abstract
Neonatal bacterial meningitis is a life-threatening disease in newborns, and neonatal meningitis Escherichia coli (NMEC) is the second most frequent bacteria causing this disease worldwide. In order to further understand the characteristics of this pathogen, an E. coli isolate W224 N from newborns with meningitis was sequenced for detailed genetic characterization and the virulence was tested by a series of phenotypic experiments. W224 N has a circular chromosome and three plasmids. It belongs to ST95 and the serotype is O18:H7. Comparative genomic analysis showed that W224 N was closely related to E. coli neonatal meningitis isolates RS218 and NMEC O18. There are 11 genomic islands in W224 N and most of the GIs are specific to W224 N. W224 N has most of the virulence factors other neonatal meningitis isolates have. The virulence genes located both on the genome and plasmid. At the same time, we found a virulence factor cdiA only present in W224 N but absent in the other five genomes analyzed. In vitro experiment showed that W224 N has strong serum resistance ability, low biofilm formation ability and high flagellar motility. It also has a very strong toxicity to mice and amoeba. The whole genome as well as in vitro and in vivo experiments showed that W224 N is a high virulent strain. The results can help us better learn about the pathogenicity of neonatal meningitis E. coli.
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Affiliation(s)
- Cun-Wei Liu
- Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Ping Wang
- Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Guang-Na Cao
- Peking University Third Hospital, Beijing, 100191, China.
| | - Qing-Hua Zou
- Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China.
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Fujimoto Y, Inoue H, Kanda T, Ijiri M, Uemura R. Virulence-Associated Gene Profiles of Escherichia coli Isolated from Chickens with Colibacillosis in Japan and Their Correlation with Pathogenicity in Chicken Embryos. Avian Dis 2021; 65:401-405. [PMID: 34427414 DOI: 10.1637/0005-2086-65.3.401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 06/10/2021] [Indexed: 11/05/2022]
Abstract
Colibacillosis, an infectious disease of chickens, is caused by avian pathogenic Escherichia coli (APEC); however, in addition to APEC, other pathogens are also frequently isolated from chickens affected with colibacillosis. Therefore, experimental infections in chickens are necessary to evaluate the pathogenicity of APEC isolates. Recent studies have shown that embryo lethality assays can be used as an alternative method to evaluate the pathogenicity of E. coli. In this study, to determine the important virulence genes associated with the pathogenicity of E. coli, 67 strains of E. coli that possessed different combinations of eight representative virulence genes (cva/cvi, vat, tsh, iucD, papC, irp2, iss, and astA) were isolated from broilers with colibacillosis in Japan, and the chicken embryo lethal assay was conducted. The genes vat, papC, and irp2 showed strong correlation with the level of virulence in E. coli. Our study provides useful information about the important virulence-associated genes in relation to the pathogenicity of E. coli in Japanese chickens.
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Affiliation(s)
- Yoshikazu Fujimoto
- Transboundary Animal Diseases Research Center, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima-shi, Kagoshima 890-0065, Japan, .,Joint Graduate School of Veterinary Medicine, Kagoshima University, Kagoshima-shi, Kagoshima 890-0065, Japan
| | - Hideya Inoue
- Shiga Prefectural Institute of Public Health, Otsu-shi, Shiga 520-0834, Japan
| | - Takuya Kanda
- Graduate School of Medicine and Veterinary Medicine, University of Miyazaki, Kiyotake-cho, Miyazaki 889-1692, Japan
| | - Moe Ijiri
- Transboundary Animal Diseases Research Center, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima-shi, Kagoshima 890-0065, Japan
| | - Ryoko Uemura
- Department of Veterinary Sciences, Faculty of Agriculture, University of Miyazaki, Gakuenkibanadainishi, Miyazaki-shi, Miyazaki 889-2192, Japan
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5
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Bile salts regulate zinc uptake and capsule synthesis in a mastitis-associated extraintestinal pathogenic Escherichia coli strain. Infect Immun 2021; 89:e0035721. [PMID: 34228495 DOI: 10.1128/iai.00357-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Extraintestinal pathogenic Escherichia coli (ExPEC) are major causes of urinary and bloodstream infections. ExPEC reservoirs are not completely understood. Some mastitis-associated E. coli (MAEC) strains carry genes associated with ExPEC virulence, including metal scavenging, immune avoidance, and host attachment functions. In this study, we investigated the role of the high-affinity zinc uptake (znuABC) system in the MAEC strain M12. Elimination of znuABC moderately decreased fitness during mouse mammary gland infections. The ΔznuABC mutant strain exhibited an unexpected growth delay in the presence of bile salts, which was alleviated by the addition of excess zinc. We isolated ΔznuABC mutant suppressor mutants with improved growth of in bile salts, several of which no longer produced the K96 capsule made by strain M12. Addition of bile salts also reduced capsule production by strain M12 and ExPEC strain CP9, suggesting that capsule synthesis may be detrimental when bile salts are present. To better understand the role of the capsule, we compared the virulence of mastitis strain M12 with its unencapsulated ΔkpsCS mutant in two models of ExPEC disease. The wild type strain successfully colonized mouse bladders and kidneys and was highly virulent in intraperitoneal infections. Conversely, the ΔkpsCS mutant was unable to colonize kidneys and was unable to cause sepsis. These results demonstrate that some MAEC may be capable of causing human ExPEC illness. Virulence of strain M12 in these infections is dependent on its capsule. However, capsule may interfere with zinc homeostasis in the presence of bile salts while in the digestive tract.
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Newman DM, Barbieri NL, de Oliveira AL, Willis D, Nolan LK, Logue CM. Characterizing avian pathogenic Escherichia coli (APEC) from colibacillosis cases, 2018. PeerJ 2021; 9:e11025. [PMID: 33717713 PMCID: PMC7937341 DOI: 10.7717/peerj.11025] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/08/2021] [Indexed: 12/14/2022] Open
Abstract
Colibacillosis caused by avian pathogenic Escherichia coli (APEC) is a devastating disease of poultry that results in multi-million-dollar losses annually to the poultry industry. Disease syndromes associated with APEC includes colisepticemia, cellulitis, air sac disease, peritonitis, salpingitis, omphalitis, and osteomyelitis among others. A total of 61 APEC isolates collected during the Fall of 2018 (Aug-Dec) from submitted diagnostic cases of poultry diagnosed with colibacillosis were assessed for the presence of 44 virulence-associated genes, 24 antimicrobial resistance genes and 17 plasmid replicon types. Each isolate was also screened for its ability to form biofilm using the crystal violet assay and antimicrobial susceptibility to 14 antimicrobials using the NARMS panel. Overall, the prevalence of virulence genes ranged from 1.6% to >90% with almost all strains harboring genes that are associated with the ColV plasmid-the defining trait of the APEC pathotype. Overall, 58 strains were able to form biofilms and only three strains formed negligible biofilms. Forty isolates displayed resistance to antimicrobials of the NARMS panel ranging from one to nine agents. This study highlights that current APEC causing disease in poultry possess virulence and resistance traits and form biofilms which could potentially lead to challenges in colibacillosis control.
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Affiliation(s)
- Darby M Newman
- Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Nicolle L Barbieri
- Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Aline L de Oliveira
- Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Dajour Willis
- Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Lisa K Nolan
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Catherine M Logue
- Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
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American Crows as Carriers of Extra Intestinal Pathogenic E. coli and Avian Pathogenic-Like E. coli and Their Potential Impact on a Constructed Wetland. Microorganisms 2020; 8:microorganisms8101595. [PMID: 33081240 PMCID: PMC7602749 DOI: 10.3390/microorganisms8101595] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 10/04/2020] [Accepted: 10/12/2020] [Indexed: 12/29/2022] Open
Abstract
The study examines whether crows are carriers of extraintestinal pathogenic E. coli (ExPEC) and avian pathogenic E. coli (APEC)-like strains, and if wetland roost areas contribute to their spread. A total of 10 crow feces (n = 71) and 15 water E. coli isolates (n = 134) from a wetland area could be characterized as potentially ExPEC based on the presence of ≥2 of the five cardinal genes iutA, kpsMT2, papEF, pap A/C, papG, sfa/foc, and afa/dra, while six fecal and 14 water isolates could be characterized as potentially APEC-like based on the presence of plasmid associated genes: iutA, episomal iss, ompT, hlyF and iroN. A total of 32 fecal and 27 water isolates tested carried plasmids based on incompatibility typing. Plasmids from 34 of 38 isolates tested could be transferred to another E. coli strain by conjugation with the antibiotic resistance (AR) profile being transferred, indicating their potential to be transferred to indigenous and non-pathogenic strains in the wetland. APEC-like plasmids could be transferred in six of eight isolates tested. Pathogenic E. coli of importance to the medical community and poultry industry may be detected in high levels in surface water due to corvid activity. Regardless of their role in health or disease, water in wetlands and streams can serve as a media for the dissemination of AR and virulence traits of bacteria, with corvids acting as potential vectors for farther dissemination.
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8
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Deng Y, Xu L, Liu S, Wang Q, Guo Z, Chen C, Feng J. What drives changes in the virulence and antibiotic resistance of Vibrio harveyi in the South China Sea? JOURNAL OF FISH DISEASES 2020; 43:853-862. [PMID: 32557678 DOI: 10.1111/jfd.13197] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/14/2020] [Accepted: 05/15/2020] [Indexed: 06/11/2023]
Abstract
To understand the driving environmental factors in changes of bacterial virulence and antibiotic resistance, we determined the prevalence, antibiotic resistance and antibiotic resistance and virulence genes of Vibrio harveyi isolated from diseased marine fish in south coastal China. We isolated 2, 52 and 53 V. harveyi strains from Fujian, Hainan and Guangdong, respectively, and identified them by multilocus sequence analysis of 16S rRNA-toxRVh -rctB. Nine typical virulence genes were represented at a higher average in Hainan (7.39 ± 0.24) than in Guangdong (6.91 ± 0.28). Five atypical virulence genes were detected in some isolates. In particular, flaC and vvh were detected in more than 60% of isolates. Their average number was significantly higher in Hainan (2.30 ± 0.20) than in Guangdong (1.70 ± 0.10). Multidrug resistance was widespread with an average resistance to 4.57 ± 0.18 of 15 antibiotics. Both the average number of antibiotic resistance and antibiotic resistance genes were higher in Hainan (5.25 ± 0.27 and 1.11 ± 0.15, respectively) than in Guangdong (3.87 ± 0.21 and 0.75 ± 0.10, respectively). This study demonstrated that there were more virulence genes and greater drug resistance in Hainan than in Guangdong, suggesting that warmer temperature and antibiotics pollutants probably enhance antibiotic resistance and bacterial infection.
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Affiliation(s)
- Yiqin Deng
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Tropical Aquaculture Research and Development Centre, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Hainan, China
| | - Liwen Xu
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Songlin Liu
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Qian Wang
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Zhixun Guo
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Chang Chen
- Xisha/Nansha Ocean Observation and Research Station, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Juan Feng
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Tropical Aquaculture Research and Development Centre, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Hainan, China
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9
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Kaldhone PR, Carlton A, Aljahdali N, Khajanchi BK, Sanad YM, Han J, Deck J, Ricke SC, Foley SL. Evaluation of Incompatibility Group I1 (IncI1) Plasmid-Containing Salmonella enterica and Assessment of the Plasmids in Bacteriocin Production and Biofilm Development. Front Vet Sci 2019; 6:298. [PMID: 31552285 PMCID: PMC6743044 DOI: 10.3389/fvets.2019.00298] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 08/22/2019] [Indexed: 12/23/2022] Open
Abstract
Mobile genetic elements, such as plasmids, can potentially increase the ability of bacteria to infect and persist in vertebrate host cells. IncI1 plasmids are widely distributed in Salmonella from food animal sources and associated with clinically important strains. These plasmids often encode antimicrobial resistance; however, little is known about their impact on the virulence of Salmonella strains. To assess the potential impact of the plasmids on virulence, 43 IncI1-positive Salmonella isolates from human and animal sources were subjected to whole genome sequence (WGS) analyses and evaluated for their abilities to invade and persist for 48 h in Caco-2 human intestinal epithelial cells, form biofilms and encode bacteriocins. Draft WGS data were submitted to predict the presence of virulence and antimicrobial resistance genes, plasmid replicon types present, conduct plasmid multilocus sequence typing (pMLST), and core genome MLST (cgMLST) in the isolates. Caco-2 cells were infected with Salmonella strains and incubated for both one and 48 h for the invasion and persistence assays, respectively. Additionally, Salmonella isolates and IncI1 plasmid carrying transconjugants (n = 12) generated in Escherichia coli were assessed for their ability to produce biofilms and bacteriocin inhibition of growth of other bacteria. All Salmonella isolates infected Caco-2 cells and persisted in the cells at 48 hrs. Persistent cell counts were observed to be significantly higher than invasion assay cell counts in 26% of the isolates. Among the IncI1 plasmids, there were 18 pMLST types. Nearly 35% (n = 15) of Salmonella isolates produced biofilms; however, none of the IncI1-positive transconjugants produced increased biofilms compared to the recipient. Approximately 65% (n = 28) of isolates and 67% (n = 8) of IncI1-positive transconjugants were able to inhibit growth of at least one E. coli strain; however, none inhibited the growth of strains from species other than E. coli. The study characterized IncI1 positive Salmonella isolates and provided evidence about the potential contributions of IncI1 plasmids virulence phenotypes and areas where they do not. These findings should allow for more focused efforts to assess the impact of plasmids on bacterial pathophysiology and human health.
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Affiliation(s)
- Pravin R Kaldhone
- Division of Microbiology, U.S. Food and Drug Administration, National Center for Toxicological Research, Jefferson, AR, United States.,Center for Food Safety and Food Science Department, University of Arkansas, Fayetteville, AR, United States
| | - Ashlyn Carlton
- Division of Microbiology, U.S. Food and Drug Administration, National Center for Toxicological Research, Jefferson, AR, United States.,Department of Agriculture, University of Arkansas at Pine Bluff, Pine Bluff, AR, United States
| | - Nesreen Aljahdali
- Division of Microbiology, U.S. Food and Drug Administration, National Center for Toxicological Research, Jefferson, AR, United States.,Department of Biological Sciences, King Abdul-Aziz University, Jeddah, Saudi Arabia
| | - Bijay K Khajanchi
- Division of Microbiology, U.S. Food and Drug Administration, National Center for Toxicological Research, Jefferson, AR, United States
| | - Yasser M Sanad
- Division of Microbiology, U.S. Food and Drug Administration, National Center for Toxicological Research, Jefferson, AR, United States.,Department of Agriculture, University of Arkansas at Pine Bluff, Pine Bluff, AR, United States.,Veterinary Research Division, Department of Parasitology and Animal Diseases, National Research Centre, Giza, Egypt
| | - Jing Han
- Division of Microbiology, U.S. Food and Drug Administration, National Center for Toxicological Research, Jefferson, AR, United States
| | - Joanna Deck
- Division of Microbiology, U.S. Food and Drug Administration, National Center for Toxicological Research, Jefferson, AR, United States
| | - Steven C Ricke
- Center for Food Safety and Food Science Department, University of Arkansas, Fayetteville, AR, United States
| | - Steven L Foley
- Division of Microbiology, U.S. Food and Drug Administration, National Center for Toxicological Research, Jefferson, AR, United States.,Center for Food Safety and Food Science Department, University of Arkansas, Fayetteville, AR, United States
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Abstract
Extraintestinal pathogenic Escherichia coli (ExPEC) are important pathogens in humans and certain animals. Molecular epidemiological analyses of ExPEC are based on structured observations of E. coli strains as they occur in the wild. By assessing real-world phenomena as they occur in authentic contexts and hosts, they provide an important complement to experimental assessment. Fundamental to the success of molecular epidemiological studies are the careful selection of subjects and the use of appropriate typing methods and statistical analysis. To date, molecular epidemiological studies have yielded numerous important insights into putative virulence factors, host-pathogen relationships, phylogenetic background, reservoirs, antimicrobial-resistant strains, clinical diagnostics, and transmission pathways of ExPEC, and have delineated areas in which further study is needed. The rapid pace of discovery of new putative virulence factors and the increasing awareness of the importance of virulence factor regulation, expression, and molecular variation should stimulate many future molecular epidemiological investigations. The growing sophistication and availability of molecular typing methodologies, and of the new computational and statistical approaches that are being developed to address the huge amounts of data that whole genome sequencing generates, provide improved tools for such studies and allow new questions to be addressed.
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11
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Jørgensen SL, Kudirkiene E, Li L, Christensen JP, Olsen JE, Nolan L, Olsen RH. Chromosomal features of Escherichia coli serotype O2:K2, an avian pathogenic E. coli. Stand Genomic Sci 2017; 12:33. [PMID: 28496941 PMCID: PMC5424372 DOI: 10.1186/s40793-017-0245-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 04/27/2017] [Indexed: 11/10/2022] Open
Abstract
Escherichia coli causing infection outside the gastrointestinal system are referred to as extra-intestinal pathogenic E. coli. Avian pathogenic E. coli is a subgroup of extra-intestinal pathogenic E. coli and infections due to avian pathogenic E. coli have major impact on poultry production economy and welfare worldwide. An almost defining characteristic of avian pathogenic E. coli is the carriage of plasmids, which may encode virulence factors and antibiotic resistance determinates. For the same reason, plasmids of avian pathogenic E. coli have been intensively studied. However, genes encoded by the chromosome may also be important for disease manifestation and antimicrobial resistance. For the E. coli strain APEC_O2 the plasmids have been sequenced and analyzed in several studies, and E. coli APEC_O2 may therefore serve as a reference strain in future studies. Here we describe the chromosomal features of E. coli APEC_O2. E. coli APEC_O2 is a sequence type ST135, has a chromosome of 4,908,820 bp (plasmid removed), comprising 4672 protein-coding genes, 110 RNA genes, and 156 pseudogenes, with an average G + C content of 50.69%. We identified 82 insertion sequences as well as 4672 protein coding sequences, 12 predicated genomic islands, three prophage-related sequences, and two clustered regularly interspaced short palindromic repeats regions on the chromosome, suggesting the possible occurrence of horizontal gene transfer in this strain. The wildtype strain of E. coli APEC_O2 is resistant towards multiple antimicrobials, however, no (complete) antibiotic resistance genes were present on the chromosome, but a number of genes associated with extra-intestinal disease were identified. Together, the information provided here on E. coli APEC_O2 will assist in future studies of avian pathogenic E. coli strains, in particular regarding strain of E. coli APEC_O2, and aid in the general understanding of the pathogenesis of avian pathogenic E. coli.
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Affiliation(s)
- Steffen L Jørgensen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Stigboejlen 4, 1870 Frederiksberg C, Denmark
| | - Egle Kudirkiene
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Stigboejlen 4, 1870 Frederiksberg C, Denmark
| | - Lili Li
- College of Light Industry and Food Sciences, South China University of Technology, Guangdong, Zhongshan Rd, People's Republic of China
| | - Jens P Christensen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Stigboejlen 4, 1870 Frederiksberg C, Denmark
| | - John E Olsen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Stigboejlen 4, 1870 Frederiksberg C, Denmark
| | - Lisa Nolan
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, 1802 Elwood Drive, VMRI #2, Ames, IA 50011 USA
| | - Rikke H Olsen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Stigboejlen 4, 1870 Frederiksberg C, Denmark
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12
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Chalmers G, Cormier AC, Nadeau M, Côté G, Reid-Smith RJ, Boerlin P. Determinants of virulence and of resistance to ceftiofur, gentamicin, and spectinomycin in clinical Escherichia coli from broiler chickens in Québec, Canada. Vet Microbiol 2017; 203:149-157. [PMID: 28619137 DOI: 10.1016/j.vetmic.2017.02.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 02/07/2017] [Accepted: 02/10/2017] [Indexed: 11/26/2022]
Abstract
Antimicrobials are frequently used for the prevention of avian colibacillosis, with gentamicin used for this purpose in Québec until 2003. Ceftiofur was also used similarly, but voluntarily withdrawn in 2005 due to increasing resistance. Spectinomycin-lincomycin was employed as a replacement, but ceftiofur use was partially reinstated in 2007 until its definitive ban by the poultry industry in 2014. Gentamicin resistance frequency increased during the past decade in clinical Escherichia coli isolates from broiler chickens in Québec, despite this antimicrobial no longer being used. Since this increase coincided with the use of spectinomycin-lincomycin, co-selection of gentamicin resistance through spectinomycin was suspected. Therefore, relationships between spectinomycin, gentamicin, and ceftiofur resistance determinants were investigated here. The distribution of 13 avian pathogenic E. coli virulence-associated genes and their association with spectinomycin resistance were also assessed. A sample of 586 E. coli isolates from chickens with colibacillosis in Québec between 2009 and 2013 was used. The major genes identified for resistance to ceftiofur, gentamicin, and spectinomycin were blaCMY, aac(3)-VI, and aadA, respectively. The aadA and aac(3)-VI genes were strongly associated and shown to be located on a modified class 1 integron. The aadA and blaCMY genes were negatively associated, but when present together, were generally located on the same plasmids. No statistical positive association was observed between aadA and virulence genes, and virulence genes were only rarely detected on plasmids encoding spectinomycin resistance. Thus, the use of spectinomycin-lincomycin may likely select for gentamicin but not ceftiofur resistance, nor for any of the virulence-associated genes investigated.
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Affiliation(s)
- Gabhan Chalmers
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, 50 Stone Rd. E, Guelph, Ontario, N1G 2W1, Canada
| | - Ashley C Cormier
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, 50 Stone Rd. E, Guelph, Ontario, N1G 2W1, Canada
| | - Marie Nadeau
- Laboratoire d'expertise en pathologie animale du Québec, 2650 rue Einstein, Québec, Québec, G1P 4S8, Canada
| | - Geneviève Côté
- Laboratoire d'expertise en pathologie animale du Québec, 2650 rue Einstein, Québec, Québec, G1P 4S8, Canada
| | - Richard J Reid-Smith
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, 50 Stone Rd. E, Guelph, Ontario, N1G 2W1, Canada; Canadian Integrated Program for Antimicrobial Resistance Surveillance Division, Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada,160 Research Lane, Suite 103, Guelph, Ontario, N1G 5B2, Canada; Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, Ontario, N1G 2W1, Canada
| | - Patrick Boerlin
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, 50 Stone Rd. E, Guelph, Ontario, N1G 2W1, Canada.
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1α,2α-Epoxy-3β-hydroxy oleanolic acid derivatives regulation of the metabolism, haemolysis and β-lactamase gene expression in vitro and their structure-microbicidal activity relationship. Bioorg Med Chem Lett 2016; 26:3870-5. [PMID: 27436581 DOI: 10.1016/j.bmcl.2016.07.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 07/05/2016] [Accepted: 07/07/2016] [Indexed: 11/24/2022]
Abstract
Oleanolic acid (OA), one of the major pentacyclic triterpenes abundantly present in nature, is a promising compound with various biological activities, including anti-inflammatory, anti-ulcer, hepatoprotective, antidiabetic, fungicidal and antiparasitic properties. Therefore, a series of derivatives of 1α,2α-epoxy-3β-hydroxyl oleanolic acid derivatives were designed and synthesized, and their antibacterial activities were investigated in vitro. Based on these results, the compounds with antibacterial activity were screened by RT-PCR to determine whether they can regulate the expression of genes related to metabolism, haemolysis, and β-lactamase in vitro, and the structure-microbicidal activity relationship of each compound was analyzed. Our study shows that some of the modifications in the synthetic compounds, such as the introduction of an ortho-cyano-substituted benzyl group and a short chain alkyl ester at the 28-carboxyl, as well as the introduction of an acetyl group at the 3-hydroxyl group of ring A, could enhance antibacterial activity. This provides basic evidence for the optimization of 1α,2α-epoxy-3β-hydroxyl oleanolic acid derivatives. The antibacterial mechanism of the active OA derivatives appears to involve the regulation of expression of metabolism-associated genes in Escherichia coli, haemolysis-associated genes in Bacillus subtilis, metabolism-related genes in Klebsiella pneumonia and β-lactamase-associated genes in Acinetobacter baumannii. Some OA derivatives were bactericidal to three of the strains and appeared to regulate gene expression associated with metabolism, haemolysis, and β-lactamase in vitro. These newly designed OA derivatives possess unique antibacterial activities and may be potentially useful for prophylactic or therapeutic intervention of bacterial infections.
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Paixão AC, Ferreira AC, Fontes M, Themudo P, Albuquerque T, Soares MC, Fevereiro M, Martins L, de Sá MIC. Detection of virulence-associated genes in pathogenic and commensal avian Escherichia coli isolates. Poult Sci 2016; 95:1646-1652. [PMID: 26976911 DOI: 10.3382/ps/pew087] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 02/02/2016] [Indexed: 11/20/2022] Open
Abstract
Poultry colibacillosis due to Avian Pathogenic Escherichia coli (APEC) is responsible for several extra-intestinal pathological conditions, leading to serious economic damage in poultry production. The most commonly associated pathologies are airsacculitis, colisepticemia, and cellulitis in broiler chickens, and salpingitis and peritonitis in broiler breeders. In this work a total of 66 strains isolated from dead broiler breeders affected with colibacillosis and 61 strains from healthy broilers were studied. Strains from broiler breeders were typified with serogroups O2, O18, and O78, which are mainly associated with disease. The serogroup O78 was the most prevalent (58%). All the strains were checked for the presence of 11 virulence genes: 1) arginine succinyltransferase A (astA); ii) E.coli hemeutilization protein A (chuA); iii) colicin V A/B (cvaA/B); iv) fimbriae mannose-binding type 1 (fimC); v) ferric yersiniabactin uptake A (fyuA); vi) iron-repressible high-molecular-weight proteins 2 (irp2); vii) increased serum survival (iss); viii) iron-uptake systems of E.coli D (iucD); ix) pielonefritis associated to pili C (papC); x) temperature sensitive haemaglutinin (tsh), and xi) vacuolating autotransporter toxin (vat), by Multiplex-PCR. The results showed that all genes are present in both commensal and pathogenic E. coli strains. The iron uptake-related genes and the serum survival gene were more prevalent among APEC. The adhesin genes, except tsh, and the toxin genes, except astA, were also more prevalent among APEC isolates. Except for astA and tsh, APEC strains harbored the majority of the virulence-associated genes studied and fimC was the most prevalent gene, detected in 96.97 and 88.52% of APEC and AFEC strains, respectively. Possession of more than one iron transport system seems to play an important role on APEC survival.
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Affiliation(s)
- A C Paixão
- Department of Chemistry, School of Sciences and Technology, University of Évora. 7000-093 Évora, Portugal.
| | - A C Ferreira
- Instituto Nacional de Investigação Agrária e Veterinária (INIAV). Rua General Morais Sarmento, s/n 1500-311 Lisboa, Portugal
| | - M Fontes
- Sociedade Agrícola da Quinta da Freiria, Valouro Group. Quinta da Freiria, Roliça, 2540-671 Roliça, Portugal
| | - P Themudo
- Instituto Nacional de Investigação Agrária e Veterinária (INIAV). Rua General Morais Sarmento, s/n 1500-311 Lisboa, Portugal
| | - T Albuquerque
- Instituto Nacional de Investigação Agrária e Veterinária (INIAV). Rua General Morais Sarmento, s/n 1500-311 Lisboa, Portugal
| | - M C Soares
- Sociedade Agrícola da Quinta da Freiria, Valouro Group. Quinta da Freiria, Roliça, 2540-671 Roliça, Portugal
| | - M Fevereiro
- Instituto Nacional de Investigação Agrária e Veterinária (INIAV). Rua General Morais Sarmento, s/n 1500-311 Lisboa, Portugal
| | - L Martins
- Department of Veterinary Medicine, School of Sciences and Technology, and Veterinary Hospital - University of Évora. Núcleo da Mitra, 7000-093 Évora, Portugal; Institute of Mediterranean Agricultural and Environmental Science (ICAAM), University of Évora. Núcleo da Mitra, Ap. 94, 7002-554 Évora, Portugal
| | - M I Corrêa de Sá
- Instituto Nacional de Investigação Agrária e Veterinária (INIAV). Rua General Morais Sarmento, s/n 1500-311 Lisboa, Portugal
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Prevalence of ColV Plasmid-Linked Genes andIn VivoPathogenicity of Avian Strains ofEscherichia coli. Foodborne Pathog Dis 2015; 12:679-85. [DOI: 10.1089/fpd.2014.1934] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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16
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Xia L, Xia YF, Huang LR, Xiao X, Lou HY, Liu TJ, Pan WD, Luo H. Benzaldehyde Schiff bases regulation to the metabolism, hemolysis, and virulence genes expression in vitro and their structure–microbicidal activity relationship. Eur J Med Chem 2015; 97:83-93. [DOI: 10.1016/j.ejmech.2015.04.042] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Revised: 04/14/2015] [Accepted: 04/18/2015] [Indexed: 11/24/2022]
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17
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In Vivo Transmission of an IncA/C Plasmid in Escherichia coli Depends on Tetracycline Concentration, and Acquisition of the Plasmid Results in a Variable Cost of Fitness. Appl Environ Microbiol 2015; 81:3561-70. [PMID: 25769824 DOI: 10.1128/aem.04193-14] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 03/10/2015] [Indexed: 12/18/2022] Open
Abstract
IncA/C plasmids are broad-host-range plasmids enabling multidrug resistance that have emerged worldwide among bacterial pathogens of humans and animals. Although antibiotic usage is suspected to be a driving force in the emergence of such strains, few studies have examined the impact of different types of antibiotic administration on the selection of plasmid-containing multidrug resistant isolates. In this study, chlortetracycline treatment at different concentrations in pig feed was examined for its impact on selection and dissemination of an IncA/C plasmid introduced orally via a commensal Escherichia coli host. Continuous low-dose administration of chlortetracycline at 50 g per ton had no observable impact on the proportions of IncA/C plasmid-containing E. coli from pig feces over the course of 35 days. In contrast, high-dose administration of chlortetracycline at 350 g per ton significantly increased IncA/C plasmid-containing E. coli in pig feces (P < 0.001) and increased movement of the IncA/C plasmid to other indigenous E. coli hosts. There was no evidence of conjugal transfer of the IncA/C plasmid to bacterial species other than E. coli. In vitro competition assays demonstrated that bacterial host background substantially impacted the cost of IncA/C plasmid carriage in E. coli and Salmonella. In vitro transfer and selection experiments demonstrated that tetracycline at 32 μg/ml was necessary to enhance IncA/C plasmid conjugative transfer, while subinhibitory concentrations of tetracycline in vitro strongly selected for IncA/C plasmid-containing E. coli. Together, these experiments improve our knowledge on the impact of differing concentrations of tetracycline on the selection of IncA/C-type plasmids.
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18
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Piccirillo A, Giovanardi D, Dotto G, Grilli G, Montesissa C, Boldrin C, Salata C, Giacomelli M. Antimicrobial resistance and class 1 and 2 integrons inEscherichia colifrom meat turkeys in Northern Italy. Avian Pathol 2014; 43:396-405. [DOI: 10.1080/03079457.2014.943690] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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19
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Hemmis CW, Schildbach JF. Thioredoxin-like proteins in F and other plasmid systems. Plasmid 2013; 70:168-89. [PMID: 23721857 DOI: 10.1016/j.plasmid.2013.05.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 05/12/2013] [Accepted: 05/13/2013] [Indexed: 11/29/2022]
Abstract
Bacterial conjugation is the process by which a conjugative plasmid transfers from donor to recipient bacterium. During this process, single-stranded plasmid DNA is actively and specifically transported from the cytoplasm of the donor, through a large membrane-spanning assembly known as the pore complex, and into the cytoplasm of the recipient. In Gram negative bacteria, construction of the pore requires localization of a subset of structural and catalytically active proteins to the bacterial periplasm. Unlike the cytoplasm, the periplasm contains proteins that promote disulfide bond formation within or between cysteine-containing proteins. To ensure proper protein folding and assembly, bacteria employ periplasmic redox systems for thiol oxidation, disulfide bond/sulfenic acid reduction, and disulfide bond isomerization. Recent data suggest that plasmid-based proteins belonging to the disulfide bond formation family play an integral role in the conjugative process by serving as mediators in folding and/or assembly of pore complex proteins. Here we report the identification of 165 thioredoxin-like family members across 89 different plasmid systems. Using phylogenetic analysis, all but nine family members were categorized into thioredoxin-like subfamilies. In addition, we discuss the diversity, conservation, and putative roles of thioredoxin-like proteins in plasmid systems, which include homologs of DsbA, DsbB, DsbC, DsbD, DsbG, and CcmG from Escherichia coli, TlpA from Bradyrhizobium japonicum, Com1 from Coxiella burnetii, as well as TrbB and TraF from plasmid F, and the absolute conservation of a disulfide isomerase in plasmids containing homologs of the transfer proteins TraH, TraN, and TraU.
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Affiliation(s)
- Casey W Hemmis
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
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20
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Escherichia coli from cellulitis lesions in broilers. JOURNAL OF FOOD MEASUREMENT AND CHARACTERIZATION 2013. [DOI: 10.1007/s11694-013-9138-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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21
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Lima-Filho JV, Martins LV, Nascimento DCDO, Ventura RF, Batista JEC, Silva AFB, Ralph MT, Vaz RV, Rabello CBV, Silva IDMMD, Evêncio-Neto J. Zoonotic potential of multidrug-resistant extraintestinal pathogenic Escherichia coli obtained from healthy poultry carcasses in Salvador, Brazil. Braz J Infect Dis 2013; 17:54-61. [PMID: 23290470 PMCID: PMC9427334 DOI: 10.1016/j.bjid.2012.09.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Accepted: 09/12/2012] [Indexed: 11/28/2022] Open
Abstract
The zoonotic potential to cause human and/or animal infections among multidrug-resistant extraintestinal pathogenic Escherichia coli from avian origin was investigated. Twenty-seven extraintestinal pathogenic E. coli isolates containing the increased survival gene (iss) were obtained from the livers of healthy and diseased poultry carcasses at two slaughterhouses in Salvador, northeastern Brazil. The antimicrobial resistance-susceptibility profiles were conducted with antibiotics of avian and/or human use by the standardized disc-diffusion method. Antimicrobial resistance was higher for levofloxacin (51.8%), amoxicillin/clavulanic acid (70.4%), ampicillin (81.5%), cefalotin (88.8%), tetracycline (100%) and streptomycin (100%). The minimum inhibitory concentrations above the resistance breakpoints of doxycycline, neomycin, oxytetracycline and enrofloxacin reached, respectively, 88.0%, 100%, 75% and 91.7% of the isolates. Strains with high and low antimicrobial resistance were i.p. administered to Swiss mice, and histopathological examination was carried out seven days after infection. Resistance to goat and human serum complement was also evaluated. The results show that Swiss mice challenged with strain 2B (resistant to 11 antimicrobials) provoked a severe degeneration of hepatocytes besides lymphocytic infiltration in the liver, whereas the spleen showed areas of degeneration of the white and red pulp. Conversely, the spleen and liver of mice challenged with strain 4A (resistant to two antimicrobials) were morphologically preserved. In addition, complement resistance to goat and human serum was high for strain 2B and low for strain 4A. Our data show that multidrug resistance and pathogenesis can be correlated in extraintestinal pathogenic E. coli strains obtained from apparently healthy poultry carcasses, increasing the risk for human public healthy.
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Affiliation(s)
- José Vitor Lima-Filho
- Department of Biology, Universidade Federal Rural de Pernambuco, Recife, PE, Brazil.
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22
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Conjugal transfer of a virulence plasmid in the opportunistic intracellular actinomycete Rhodococcus equi. J Bacteriol 2012; 194:6790-801. [PMID: 23042997 DOI: 10.1128/jb.01210-12] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rhodococcus equi is a facultative intracellular, Gram-positive, soilborne actinomycete which can cause severe pyogranulomatous pneumonia with abscessation in young horses (foals) and in immunocompromised people, such as persons with AIDS. All strains of R. equi isolated from foals and approximately a third isolated from humans contain a large, ~81-kb plasmid which is essential for the intramacrophage growth of the organism and for virulence in foals and murine in vivo model systems. We found that the entire virulence plasmid could be transferred from plasmid-containing strains of R. equi (donor) to plasmid-free R. equi strains (recipient) at a high frequency and that plasmid transmission reestablished the capacity for intracellular growth in macrophages. Plasmid transfer required living cells and cell-to-cell contact and was unaffected by the presence of DNase, factors pointing to conjugation as the major means of genetic transfer. Deletion of a putative relaxase-encoding gene, traA, located in the proposed conjugative region of the plasmid, abolished plasmid transfer. Reversion of the traA mutation restored plasmid transmissibility. Finally, plasmid transmission to other Rhodococcus species and some additional related organisms was demonstrated. This is the first study showing a virulence plasmid transfer in R. equi, and it establishes a mechanism by which the virulence plasmid can move among bacteria in the soil.
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Monecke S, Engelmann I, Archambault M, Coleman DC, Coombs GW, Cortez de Jäckel S, Pelletier-Jacques G, Schwarz S, Shore AC, Slickers P, Ehricht R. Distribution of SCCmec-associated phenol-soluble modulin in staphylococci. Mol Cell Probes 2012; 26:99-103. [DOI: 10.1016/j.mcp.2012.01.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 12/16/2011] [Accepted: 01/03/2012] [Indexed: 10/14/2022]
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24
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Matter LB, Barbieri NL, Nordhoff M, Ewers C, Horn F. Avian pathogenic Escherichia coli MT78 invades chicken fibroblasts. Vet Microbiol 2011; 148:51-9. [DOI: 10.1016/j.vetmic.2010.08.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Revised: 08/06/2010] [Accepted: 08/16/2010] [Indexed: 10/19/2022]
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25
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Evaluation of virulence factor profiling in the characterization of veterinary Escherichia coli isolates. Appl Environ Microbiol 2010; 76:7509-13. [PMID: 20889790 DOI: 10.1128/aem.00726-10] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Escherichia coli has been used as an indicator organism for fecal contamination of water and other environments and is often a commensal organism in healthy animals, yet a number of strains can cause disease in young or immunocompromised animals. In this study, 281 E. coli isolates from bovine, porcine, chicken, canine, equine, feline, and other veterinary sources were analyzed by BOXA1R PCR and by virulence factor profiling of 35 factors to determine whether they had utility in identifying the animal source of the isolates. The results of BOXA1R PCR analysis demonstrated a high degree of diversity; less than half of the isolates fell into one of 27 clusters with at least three isolates (based on 90% similarity). Nearly 60% of these clusters contained isolates from more than one animal source. Conversely, the results of virulence factor profiling demonstrated clustering by animal source. Three clusters, named Bovine, Chicken, and Porcine, based on discriminant components analysis, were represented by 90% or more of the respective isolates. A fourth group, termed Companion, was the most diverse, containing at least 84% of isolates from canine, feline, equine, and other animal sources. Based on these results, it appears that virulence factor profiling may have utility, helping identify the likely animal host species sources of certain E. coli isolates.
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Suojala L, Pohjanvirta T, Simojoki H, Myllyniemi AL, Pitkälä A, Pelkonen S, Pyörälä S. Phylogeny, virulence factors and antimicrobial susceptibility of Escherichia coli isolated in clinical bovine mastitis. Vet Microbiol 2010; 147:383-8. [PMID: 20729012 DOI: 10.1016/j.vetmic.2010.07.011] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Revised: 07/12/2010] [Accepted: 07/14/2010] [Indexed: 10/19/2022]
Abstract
The aim of this study was to identify specific phylogeny groups, virulence genes or antimicrobial resistance traits of Escherichia coli isolated in bovine mastitis associated to clinical signs, persistence of intramammary infection in the quarter and recovery from mastitis. A total of 154 E. coli isolates from bovine clinical mastitis, 144 from the acute stage and 10 from follow-up samples 3 weeks later, originating from 144 cows in 65 dairy herds in Southern Finland were investigated. Phylogeny groups and virulence genes of the isolates were determined using polymerase chain reaction, and antimicrobial susceptibility using the VetMIC™ microdilution method. In ten cows (11.8%), infection persisted, confirmed by re-isolation of the same pulsed-field gel electrophoresis type from the affected quarter at 3 weeks post-treatment. The majority of isolates, 119 (82.6%), belonged to phylogeny group A, which mainly consisted of commensal strains. Altogether 56 isolates (38.9%) had at least one virulence gene detected. Most common virulence genes detected were irp2, iucD, papC iss; genes svg, stx1, stx2, cnf1 and hlyA were not found. Combinations of virulence genes varied greatly. Forty (27.8%) of the 144 E. coli isolates showed resistance to at least one antimicrobial tested. None of the studied phylogeny groups, virulence factors or antimicrobial resistance traits was associated with clinical signs, persistence of intramammary infection or clinical recovery from mastitis. The results support the conclusion that mastitis-causing E. coli bacteria are typical commensals.
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Affiliation(s)
- Leena Suojala
- Department of Production Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Paroninkuja 20, FI-04920 Saarentaus, Finland.
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Role of antimicrobial selective pressure and secondary factors on antimicrobial resistance prevalence in Escherichia coli from food-producing animals in Japan. J Biomed Biotechnol 2010; 2010:180682. [PMID: 20589071 PMCID: PMC2879543 DOI: 10.1155/2010/180682] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2009] [Accepted: 03/16/2010] [Indexed: 12/04/2022] Open
Abstract
The use of antimicrobial agents in the veterinary field affects the emergence, prevalence, and dissemination of antimicrobial resistance in bacteria isolated from food-producing animals. To control the emergence, prevalence, and dissemination of antimicrobial resistance, it is necessary to implement appropriate actions based on scientific evidence. In Japan, the Japanese Veterinary Antimicrobial Resistance Monitoring System (JVARM) was established in 1999 to monitor the antimicrobial susceptibility of foodborne and commensal bacteria from food-producing animals. The JVARM showed that the emergence and prevalence of resistant Escherichia coli were likely linked to the therapeutic antimicrobial use in food-producing animals through not only direct selection of the corresponding resistance but also indirect selections via cross-resistance and coresistance. In addition, relevant factors such as host animals and bacterial properties might affect the occurrence and prevalence of antimicrobial-resistant E. coli under the selective pressure from antimicrobial usage. This paper reviews the trends in antimicrobial resistance in E. coli and consumption of antimicrobials agents in Japan and introduces the relationship between antimicrobial usage and prevalence of antimicrobial-resistant bacteria, from food-producing animals under the JVARM program. In this paper, we will provide the underlying information about the significant factors that can help control antimicrobial resistance in bacteria in veterinary medicine.
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Abreu DLDC, Franco RM, Nascimento ERD, Pereira VLDA, Alves FMX, Almeida JFD. Perfil de sensibilidade antimicrobiana e detecção do gene ISS pela reação em cadeia da polimerase na tipificação de Escherichia coli patogênica em codornas de corte sob inspeção sanitária. PESQUISA VETERINÁRIA BRASILEIRA 2010. [DOI: 10.1590/s0100-736x2010000500006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A patogenicidade das cepas de Escherichia coli está relacionada à expressão de fatores de virulência encontrados em elementos genéticos denominados plasmídios. O patotipo APEC, responsável por diferentes tipos de doenças em aves, pode apresentar o gene iss que aumenta a resistência das cepas de E. coli aos efeitos líticos do soro, além da resistência a diversos antimicrobianos. Este estudo foi conduzido para detectar E. coli em traquéias de codornas destinadas ao abate e avaliar, pela presença do gene iss e o perfil de susceptibilidade antimicrobiana, o potencial patogênico para aves e humanos dos isolados obtidos. Foram coletadas 180 traquéias de codornas para detecção de E. coli, determinação do perfil de resistência a agentes antimicrobianos e posterior detecção, por reação em cadeia da polimerase (PCR), do gene iss. Das traquéias analisadas, 8,9 % (16/180) foram positivas para E. coli, sendo obtidos 20 isolados deste agente. A maioria dos isolados foi resistente à Tetraciclina (16/20), seguida pela Ceftazidima (13/20) e Ácido Nalidíxico (12/20), sendo apenas um resistente à Amoxicilina. A detecção do gene iss ocorreu em 55% (11/20) dos isolados. A presença do gene iss e a resistência a múltiplos antimicrobianos dos isolados obtidos neste estudo pode indicar um possível potencial patogênico das cepas de E. coli tanto para codornas quanto para outros tipos de aves e animais e mesmo para o ser humano que fique em contato com as mesmas.
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Abstract
Bacterial plasmids are self-replicating, extrachromosomal elements that are key agents of change in microbial populations. They promote the dissemination of a variety of traits, including virulence, enhanced fitness, resistance to antimicrobial agents, and metabolism of rare substances. Escherichia coli, perhaps the most studied of microorganisms, has been found to possess a variety of plasmid types. Included among these are plasmids associated with virulence. Several types of E. coli virulence plasmids exist, including those essential for the virulence of enterotoxigenic E. coli, enteroinvasive E. coli, enteropathogenic E. coli, enterohemorrhagic E. coli, enteroaggregative E. coli, and extraintestinal pathogenic E. coli. Despite their diversity, these plasmids belong to a few plasmid backbones that present themselves in a conserved and syntenic manner. Thanks to some recent research, including sequence analysis of several representative plasmid genomes and molecular pathogenesis studies, the evolution of these virulence plasmids and the implications of their acquisition by E. coli are now better understood and appreciated. Here, work involving each of the E. coli virulence plasmid types is summarized, with the available plasmid genomic sequences for several E. coli pathotypes being compared in an effort to understand the evolution of these plasmid types and define their core and accessory components.
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Sequence analysis and characterization of a transferable hybrid plasmid encoding multidrug resistance and enabling zoonotic potential for extraintestinal Escherichia coli. Infect Immun 2010; 78:1931-42. [PMID: 20160015 DOI: 10.1128/iai.01174-09] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
ColV plasmids of extraintestinal pathogenic Escherichia coli (ExPEC) encode a variety of fitness and virulence factors and have long been associated with septicemia and avian colibacillosis. These plasmids are found significantly more often in ExPEC, including ExPEC associated with human neonatal meningitis and avian colibacillosis, than in commensal E. coli. Here we describe pAPEC-O103-ColBM, a hybrid RepFIIA/FIB plasmid harboring components of the ColV pathogenicity island and a multidrug resistance (MDR)-encoding island. This plasmid is mobilizable and confers the ability to cause septicemia in chickens, the ability to cause bacteremia resulting in meningitis in the rat model of human disease, and the ability to resist the killing effects of multiple antimicrobial agents and human serum. The results of a sequence analysis of this and other ColV plasmids supported previous findings which indicated that these plasmid types arose from a RepFIIA/FIB plasmid backbone on multiple occasions. Comparisons of pAPEC-O103-ColBM with other sequenced ColV and ColBM plasmids indicated that there is a core repertoire of virulence genes that might contribute to the ability of some ExPEC strains to cause high-level bacteremia and meningitis in a rat model. Examination of a neonatal meningitis E. coli (NMEC) population revealed that approximately 58% of the isolates examined harbored ColV-type plasmids and that 26% of these plasmids had genetic contents similar to that of pAPEC-O103-ColBM. The linkage of the ability to confer MDR and the ability contribute to multiple forms of human and animal disease on a single plasmid presents further challenges for preventing and treating ExPEC infections.
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Characterization of the contribution to virulence of three large plasmids of avian pathogenic Escherichia coli chi7122 (O78:K80:H9). Infect Immun 2010; 78:1528-41. [PMID: 20086082 DOI: 10.1128/iai.00981-09] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Despite the fact that the presence of multiple large plasmids is a defining feature of extraintestinal pathogenic Escherichia coli (ExPEC), such as avian pathogenic E. coli (APEC), and despite the fact that these bacteria pose a considerable threat to both human and animal health, characterization of these plasmids is still limited. In this study, after successfully curing APEC of its plasmids, we were able to investigate, for the first time, the contribution to virulence of three plasmids, pAPEC-1 (103 kb), pAPEC-2 (90 kb), and pAPEC-3 (60 kb), from APEC strain chi7122 individually as well as in all combinations in the wild-type background. Characterization of the different strains revealed unique features of APEC virulence. In vivo assays showed that curing the three plasmids resulted in severe attenuation of virulence. The presence of different plasmids and combinations of plasmids resulted in strains with different pathotypes and levels of virulence, reflecting the diversity of APEC strains associated with colibacillosis in chickens. Unexpectedly, our results associated the decrease in growth of some strains in some media with the virulence of APEC, and the mechanism was associated with some combinations of plasmids that included pAPEC-1. This study provided new insights into the roles of large plasmids in the virulence, growth, and evolution of APEC by showing for the first time that both the nature of plasmids and combinations of plasmids have an effect on these phenomena. It also provided a plausible explanation for some of the conflicting results related to the virulence of ExPEC strains. This study should help us understand the virulence of other ExPEC strains and design more efficient infection control strategies.
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Nakazato G, Campos TAD, Stehling EG, Brocchi M, Silveira WDD. Virulence factors of avian pathogenic Escherichia coli (APEC). PESQUISA VETERINARIA BRASILEIRA 2009. [DOI: 10.1590/s0100-736x2009000700001] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Avian pathogenic Escherichia coli (APEC) strains cause a great diversity of diseases in birds and are responsible for great economic losses in the avian industry. To date, several studies have been carried out to better understand the APEC pathogenesis for a possible development of tools which could prevent the economics losses caused by these strains. This review discusses the virulence factors described do date to be expressed by these strains and the advances made to understand and identify virulence determinants present in APEC.
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The pattern, association with multidrug-resistance and transferability of plasmid-mediated tetracycline resistance inEscherichia coli isolates from the poultry in Iran. ANN MICROBIOL 2009. [DOI: 10.1007/bf03178318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Zhao L, Gao S, Huan H, Xu X, Zhu X, Yang W, Gao Q, Liu X. Comparison of virulence factors and expression of specific genes between uropathogenic Escherichia coli and avian pathogenic E. coli in a murine urinary tract infection model and a chicken challenge model. MICROBIOLOGY-SGM 2009; 155:1634-1644. [PMID: 19372154 DOI: 10.1099/mic.0.024869-0] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Avian pathogenic Escherichia coli (APEC) and uropathogenic E. coli (UPEC) establish infections in extraintestinal habitats of different hosts. As the diversity, epidemiological sources and evolutionary origins of extraintestinal pathogenic E. coli (ExPEC) are so far only partially defined, in the present study,100 APEC isolates and 202 UPEC isolates were compared by their content of virulence genes and phylogenetic groups. The two groups showed substantial overlap in terms of their serogroups, phylogenetic groups and virulence genotypes, including their possession of certain genes associated with large transmissible plasmids of APEC. In a chicken challenge model, both UPEC U17 and APEC E058 had similar LD(50), demonstrating that UPEC U17 had the potential to cause significant disease in poultry. To gain further information about the similarities between UPEC and APEC, the in vivo expression of 152 specific genes of UPEC U17 and APEC E058 in both a murine urinary tract infection (UTI) model and a chicken challenge model was compared with that of these strains grown statically to exponential phase in rich medium. It was found that in the same model (murine UTI or chicken challenge), various genes of UPEC U17 and APEC E058 showed a similar tendency of expression. Several iron-related genes were upregulated in the UTI model and/or chicken challenge model, indicating that iron acquisition is important for E. coli to survive in blood or the urinary tract. Based on these results, the potential for APEC to act as human UPEC or as a reservoir of virulence genes for UPEC should be considered. Further, this study compared the transcriptional profile of virulence genes among APEC and UPEC in vivo.
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Affiliation(s)
- Lixiang Zhao
- Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China
| | - Song Gao
- Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China
| | - Haixia Huan
- Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China
| | - Xiaojing Xu
- Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China
| | - Xiaoping Zhu
- College of Clinical Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China
| | - Weixia Yang
- College of Clinical Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China
| | - Qingqing Gao
- Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China
| | - Xiufan Liu
- Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China
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Full sequence and comparative analysis of the plasmid pAPEC-1 of avian pathogenic E. coli chi7122 (O78:K80:H9). PLoS One 2009; 4:e4232. [PMID: 19156210 PMCID: PMC2626276 DOI: 10.1371/journal.pone.0004232] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2008] [Accepted: 12/06/2008] [Indexed: 12/04/2022] Open
Abstract
Background Extra-intestinal pathogenic E. coli (ExPEC), including Avian Pathogenic E. coli (APEC), are very diverse. They cause a complex of diseases in Human, animals, and birds. Even though large plasmids are often associated with the virulence of ExPEC, their characterization is still in its infancy. Methodology/Principal Findings We fully sequenced and analyzed the large plasmid pAPEC-1 (103,275-bp) associated with the APEC strain χ7122, from worldwide serogroup O78∶K80∶H9. A putative virulence region spanning an 80-kb region of pAPEC-1 possesses four iron acquisition systems (iutA iucABCD, sitABCD, iroBCDN, and temperature-sensitive hemagglutinin tsh), a colicin V operon, increasing serum sensitivity iss, ompT, hlyF, and etsABC. Thirty three ORFs in pAPEC-1 are identified as insertion sequences (ISs) that belong to nine families with diverse origins. The full length of the transfer region in pAPEC-1 (11 kb) is shorter compared to the tra region of other sequenced F plasmids; the absence of some tra genes in pAPEC-1 affects its self-transferability, and the conjugative function of the plasmid was effective only in the presence of other plasmids. Two-replicon systems, repFIIA-repFIC and repFIB, and two post-segregational systems, srnB and hok/sok, are also present in the sequence of pAPEC-1. The comparison of the pAPEC-1 sequence with the two available plasmid sequences reveals more gene loss and reorganization than previously appreciated. The presence of pAPEC-1-associated genes is assessed in human ExPEC by PCR. Many patterns of association between genes are found. Conclusions/Significance The pathotype typical of pAPEC-1 was present in some human strains, which indicates a horizontal transfer between strains and the zoonotic risk of APEC strains. ColV plasmids could have common virulence genes that could be acquired by transposition, without sharing genes of plasmid function.
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Ananias M, Yano T. Serogroups and virulence genotypes of Escherichia coli isolated from patients with sepsis. Braz J Med Biol Res 2008; 41:877-83. [DOI: 10.1590/s0100-879x2008001000008] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2007] [Accepted: 09/03/2008] [Indexed: 11/22/2022] Open
Affiliation(s)
- M. Ananias
- Universidade Estadual de Campinas, Brasil
| | - T. Yano
- Universidade Estadual de Campinas, Brasil
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Insights into the environmental resistance gene pool from the genome sequence of the multidrug-resistant environmental isolate Escherichia coli SMS-3-5. J Bacteriol 2008; 190:6779-94. [PMID: 18708504 DOI: 10.1128/jb.00661-08] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The increasing occurrence of multidrug-resistant pathogens of clinical and agricultural importance is a global public health concern. While antimicrobial use in human and veterinary medicine is known to contribute to the dissemination of antimicrobial resistance, the impact of microbial communities and mobile resistance genes from the environment in this process is not well understood. Isolated from an industrially polluted aquatic environment, Escherichia coli SMS-3-5 is resistant to a record number of antimicrobial compounds from all major classes, including two front-line fluoroquinolones (ciprofloxacin and moxifloxacin), and in many cases at record-high concentrations. To gain insights into antimicrobial resistance in environmental bacterial populations, the genome of E. coli SMS-3-5 was sequenced and compared to the genome sequences of other E. coli strains. In addition, selected genetic loci from E. coli SMS-3-5 predicted to be involved in antimicrobial resistance were phenotypically characterized. Using recombinant vector clones from shotgun sequencing libraries, resistance to tetracycline, streptomycin, and sulfonamide/trimethoprim was assigned to a single mosaic region on a 130-kb plasmid (pSMS35_130). The remaining plasmid backbone showed similarity to virulence plasmids from avian-pathogenic E. coli (APEC) strains. Individual resistance gene cassettes from pSMS35_130 are conserved among resistant bacterial isolates from multiple phylogenetic and geographic sources. Resistance to quinolones was assigned to several chromosomal loci, mostly encoding transport systems that are also present in susceptible E. coli isolates. Antimicrobial resistance in E. coli SMS-3-5 is therefore dependent both on determinants acquired from a mobile gene pool that is likely available to clinical and agricultural pathogens, as well, and on specifically adapted multidrug efflux systems. The association of antimicrobial resistance with APEC virulence genes on pSMS35_130 highlights the risk of promoting the spread of virulence through the extensive use of antibiotics.
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Dziva F, Stevens MP. Colibacillosis in poultry: unravelling the molecular basis of virulence of avian pathogenicEscherichia coliin their natural hosts. Avian Pathol 2008; 37:355-66. [DOI: 10.1080/03079450802216652] [Citation(s) in RCA: 168] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Tyler CD, Lichti CF, Diekman AB, Foley SL. Evaluation of Differentially Expressed Proteins Following Serum Exposure in Avian Pathogenic Escherichia coli. Avian Dis 2008; 52:23-7. [DOI: 10.1637/8026-053107-reg] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Trampel DW, Wannemuehler Y, Nolan LK. Characterization of Escherichia coli isolates from peritonitis lesions in commercial laying hens. Avian Dis 2008; 51:840-4. [PMID: 18251391 DOI: 10.1637/7797-111906-regr1.1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Five clinically normal chickens from three farms (farm A, farm B, and farm C), for a total of 15 clinically normal chickens, were examined bacteriologically. In a similar manner, five dead chickens with lesions of peritonitis from each of the same three commercial egg-laying operations were selected for bacterial culturing. Escherichia coli were isolated from the cloaca in 14 of 15 healthy chickens and from all 15 chickens with peritonitis. Oviducts of normal chickens did not contain E. coli (0/15) whereas oviducts from 13 of 15 hens with peritonitis were positive for this pathogen. No lesions and no E. coli (0/15) were found in the peritoneal cavity of healthy hens, but peritonitis lesions from 13 of 15 dead chickens yielded E. coli. On farm A and farm B, a flock consisted of all chickens within a single house and all chickens in each flock were of the same age and same genetic strain. In flock 1 from farm A, all five E. coli isolates from the oviduct and all five isolates from the peritoneal cavity were serogrouped as O78; contained the virulence genes iroN, sitA, iutA, tsh, and iss; and belonged to phylogenetic group A. In flock 2 from farm B, all four E. coli isolates from the oviduct and all four isolates from the peritoneal cavity were serogrouped as O111; contained virulence genes iroN, sitA, iutA, traT, iss, and ompT; and belonged to phylogenetic group D. These data suggest that all chickens with peritonitis in a single flock on farms A and B were likely infected by the same E. coli strain. Escherichia coli isolates from the magnum and peritoneum had the same serogroup, virulence genotype, and phylogenetic group, which is consistent with an ascending infection from the oviduct to the peritoneal cavity.
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Affiliation(s)
- Darrell W Trampel
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa 50011, USA.
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Skyberg JA, Johnson TJ, Nolan LK. Mutational and transcriptional analyses of an avian pathogenic Escherichia coli ColV plasmid. BMC Microbiol 2008; 8:24. [PMID: 18230176 PMCID: PMC2270849 DOI: 10.1186/1471-2180-8-24] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2007] [Accepted: 01/29/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Previously we described a 184-kb ColV plasmid, pAPEC-O2-ColV, that contributed to the ability of an E. coli to kill avian embryos, grow in human urine, and colonize the murine kidney. Here, the roles of several genes encoded by this plasmid in virulence were assessed using mutational and transcriptional analyses. METHODS Genes chosen for deletion were iss, tsh, iutA, iroN, sitA, and cvaB. In addition, a 35-kb region of the plasmid, containing iss, tsh, and the ColV and iro operons, along with a 15-kb region containing both the aerobactin and sit operons, were deleted. Mutants were compared to the wild-type (APEC O2) for lethality to chick embryos and growth in human urine. Expression of the targeted genes was also assessed under these same conditions using RT-PCR RESULTS: No significant differences between the mutants and the wild-type in these phenotypic traits were detected. However, genes encoding known or predicted iron transport systems were up-regulated during growth in human urine, as compared to growth in LB broth, while iss, hlyF, and iroN were strongly up-regulated in chick embryos. CONCLUSION While no difference was observed between the mutant strains and their wild-type parent in the phenotypic traits assayed, we reasoned that some compensatory virulence mechanism, insensitivity of the virulence assays, or other factor could have obscured changes in the virulence of the mutants. Indeed we found several of these genes to be up-regulated in human urine and/or in the chick embryo, suggesting that certain genes linked to ColV plasmids are involved in the establishment of avian extraintestinal infection.
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Affiliation(s)
- Jerod A Skyberg
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA.
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Lynne AM, Skyberg JA, Logue CM, Doetkott C, Foley SL, Nolan LK. Characterization of a series of transconjugant mutants of an avian pathogenic Escherichia coli isolate for resistance to serum complement. Avian Dis 2007; 51:771-6. [PMID: 17992940 DOI: 10.1637/0005-2086(2007)51[771:coasot]2.0.co;2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Colibacillosis, caused by avian pathogenic Escherichia coli (APEC) is a major problem for the poultry industry resulting in significant losses annually. Previous work in our lab and by others has shown that the increased serum survival gene (iss) is a common trait associated with the virulence of APEC. This gene was first described for its contributions to E. coli serum resistance. However, recently published research has called the contribution of iss to this trait into question. In the present study, the level of serum resistance conferred on an E. coli isolate by iss is examined. Additionally, the contribution of lambda bor gene to E. coli serum resistance is studied, as iss is thought to be derived from bor and bor occurs commonly among E. coli. To better understand the iss and bor contributions to serum resistance, a series of iss and bor mutants was generated. An iss deletion (iss-) mutant showed a significant drop in its resistance to serum. Similarly, a bor mutant showed a drop in serum resistance but not as drastic as that observed with the iss mutant, suggesting that iss contributes more to serum resistance than bor in this E. coli strain. Also, when iss was reintroduced into the iss- mutant the wild-type level of serum resistance was restored, confirming that the deletion of iss was responsible for the change in resistance seen in the mutant.
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Affiliation(s)
- Aaron M Lynne
- National Farm Medicine Center, Marshfield Clinic Research Foundation, Marshfield, WI 54449, USA
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Foley SL, Zhao S, Walker RD. Comparison of molecular typing methods for the differentiation of Salmonella foodborne pathogens. Foodborne Pathog Dis 2007; 4:253-76. [PMID: 17883310 DOI: 10.1089/fpd.2007.0085] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Bacteria belonging to the genus Salmonella are among the leading causes of foodborne disease of bacterial etiology. These bacteria are also widely disseminated throughout the animal kingdom. The ability to identify the food source from which a human pathogen originated would be of great value in reducing the incidence of foodborne disease and the extent of disease outbreaks due to Salmonella. To date, efforts to identify the origin of these pathogens have centered on phenotypic and genotypic characterization of Salmonella isolates. This review focuses molecular or genotypic techniques that are currently being used for typing, and examines their strengths and weaknesses for determining the source of Salmonella foodborne infections.
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Affiliation(s)
- Steven L Foley
- National Farm Medicine Center, Marshfield Clinic Research Foundation, Marshfield, Wisconsin 54449, USA.
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Lynne AM, Skyberg JA, Logue CM, Nolan LK. Detection of Iss and Bor on the surface of Escherichia coli. J Appl Microbiol 2007; 102:660-6. [PMID: 17309614 DOI: 10.1111/j.1365-2672.2006.03133.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS To confirm the presence of Iss and Bor on the outer membrane of Escherichia coli using Western blots of outer membrane protein (OMP) preparations and fluorescence microscopy, and explore the use of fluorescence microscopy for the detection of avian pathogenic E. coli (APEC) and diagnosis of avian colibacillosis. METHODS AND RESULTS Knockout mutants of iss and bor were created using a one-step recombination of target genes with PCR-generated antibiotic resistance cassettes. Anti-Iss monoclonal antibodies (Mabs) that cross-react with Bor protein were used to study the mutants relative to the wild-type organism. These Mabs were used as reagents to study OMP preparations of the mutants with Western blotting and intact E. coli cells with fluorescence microscopy. Iss and Bor were detected in Western blots of OMP preparations of the wild type. Also, Iss was detected on Deltabor mutants, and Bor was detected on Deltaiss mutants. Iss and Bor were also detected on the surface of the intact, wild-type cells and mutants using fluorescence microscopy. CONCLUSIONS These results demonstrate that Bor and Iss are exposed on E. coli's outer membrane where they may be recognized by the host's immune system. SIGNIFICANCE AND IMPACT OF THE STUDY To our knowledge, this is the first report confirming Iss' location in the outer membrane of an E. coli isolate. Such surface exposure has implications for the use of these Mabs for APEC detection and colibacillosis control.
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Affiliation(s)
- A M Lynne
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
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Fakhr MK, Sherwood JS, Thorsness J, Logue CM. Molecular characterization and antibiotic resistance profiling of Salmonella isolated from retail Turkey meat products. Foodborne Pathog Dis 2007; 3:366-74. [PMID: 17199518 DOI: 10.1089/fpd.2006.3.366] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Contaminated poultry meat has been identified as one of the principal foodborne sources of Salmonella. Molecular characterization of Salmonella is important in addressing methods to control this pathogen. Seventy-four retail turkey meat samples were collected from various stores in Fargo, North Dakota in the fall of 2003. Salmonella was recovered from 30 samples using the standard conventional culture method (FSIS, USDA). Isolated Salmonella were characterized by serotyping, pulsed-field gel electrophoresis (PFGE) analysis, plasmid analysis, and antibiotic resistance profiling. Five serotypes were identified among the isolates: Newport (n = 12), Hadar (n = 8), Heidelberg (n = 7), 4,12:nonmotile (n = 2), and Reading (n = 1). XbaI PFGE analysis revealed 13 PFGE types and succeeded in grouping the isolates according to their serotypes. Plasmid profiling identified 5 plasmid types (with 1 or 2 plasmids) among eleven isolates that harbored plasmids. Seventeen isolates were resistant to antibiotics. The Heidelberg serotype showed resistance to multiple antibiotics: 1 isolate had resistance to gentamicin, sulfamethoxazole, and streptomycin, and 6 isolates had resistance to tetracycline, gentamycin, sulfamethoxazole, kanamycin, and streptomycin. The Hadar serotype isolates were resistant to 2 or 3 antibiotics: tetracycline and streptomycin (1 isolate); tetracycline and kanamycin (1 isolate); and tetracycline, kanamycin, and streptomycin (6 isolates). The 4,12:nonmotile serotype isolates showed resistance to tetracycline only. The Newport and the Reading serotypes were susceptible to all 16 of the antimicrobials tested.
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Affiliation(s)
- Mohamed K Fakhr
- Department of Veterinary and Microbiological Sciences, North Dakota State University, Fargo, North Dakota 58105, USA
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Johnson TJ, Wannemuehler YM, Johnson SJ, Logue CM, White DG, Doetkott C, Nolan LK. Plasmid replicon typing of commensal and pathogenic Escherichia coli isolates. Appl Environ Microbiol 2007; 73:1976-83. [PMID: 17277222 PMCID: PMC1828809 DOI: 10.1128/aem.02171-06] [Citation(s) in RCA: 261] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Despite the critical role of plasmids in horizontal gene transfer, few studies have characterized plasmid relatedness among different bacterial populations. Recently, a multiplex PCR replicon typing protocol was developed for classification of plasmids occurring in members of the Enterobacteriaceae. Here, a simplified version of this replicon typing procedure which requires only three multiplex panels to identify 18 plasmid replicons is described. This method was used to screen 1,015 Escherichia coli isolates of avian, human, and poultry meat origin for plasmid replicon types. Additionally, the isolates were assessed for their content of several colicin-associated genes. Overall, a high degree of plasmid variability was observed, with 221 different profiles occurring among the 1,015 isolates examined. IncFIB plasmids were the most common type identified, regardless of the source type of E. coli. IncFIB plasmids occurred significantly more often in avian pathogenic E. coli (APEC) and retail poultry E. coli (RPEC) than in uropathogenic E. coli (UPEC) and avian and human fecal commensal E. coli isolates (AFEC and HFEC, respectively). APEC and RPEC were also significantly more likely than UPEC, HFEC, and AFEC to possess the colicin-associated genes cvaC, cbi, and/or cma in conjunction with one or more plasmid replicons. The results suggest that E. coli isolates contaminating retail poultry are notably similar to APEC with regard to plasmid profiles, with both generally containing multiple plasmid replicon types in conjunction with colicin-related genes. In contrast, UPEC and human and avian commensal E. coli isolates generally lack the plasmid replicons and colicin-related genes seen in APEC and RPEC, suggesting limited dissemination of such plasmids among these bacterial populations.
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Affiliation(s)
- Timothy J Johnson
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, 1802 Elwood Drive, VMRI #2, Iowa State University, Ames, IA 50011, USA
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Nógrády N, Pászti J, Pikó H, Nagy B. Class 1 integrons and their conjugal transfer with and without virulence-associated genes in extra-intestinal and intestinal Escherichia coli of poultry. Avian Pathol 2006; 35:349-56. [PMID: 16854651 DOI: 10.1080/03079450600827007] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Multiple-drug resistance in enteric bacteria is frequently associated with integrons. To determine whether integrons may play a role in avian pathogenic Escherichia coli, isolates of extra-intestinal (n = 27) and intestinal (n = 40) E. coli from dead chicks and turkey poults were analysed for the presence of class 1 integrons and of the virulence-associated genes iss, tsh and colV. Eleven extra-intestinal strains possessed a 1.0 kb class 1 integron with a variable region of aadA1 and were resistant to tetracycline. These traits were indicative of the presence of the Tn21 transposon, which was confirmed by polymerase chain reaction. All extra-intestinal strains had the colV, iss and tsh genes, but none of these genes were cotransferred with the 1.0 kb integron when conjugal transferability was tested. The integron content of the intestinal strains showed considerable variability: one or two of four different class 1 integrons, which varied from 1.0 to 2.4 kb in size, were detected in the 11 strains. The aadA7 gene of the 1.0 kb integron, the dfrA1-aadA1 genes of the 1.6 kb integron and the folA-catB3-aadA5 genes of the 2.4 kb integron were identical to those described by other workers. However, the orfIN682-dhfrV-orfD gene cassette arrangement of the 1.5 kb integron of an intestinal strain of serogroup O5 had no similarity to any previously reported integrons. Conjugal transfer of the 1.6 and 2.4 kb integrons was successful, and in a serogroup O33 intestinal E. coli strain the iss gene was apparently cotransferred with a 1.6 kb integron. The 1.0 and 1.5 kb integrons were not transferable. Our data suggest that intestinal E. coli strains of poultry may be a reservoir for emerging multiresistant strains of avian pathogenic E. coli.
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Affiliation(s)
- Noémi Nógrády
- Department of Phage-typing and Molecular Epidemiology, Johan Béla National Center for Epidemiology, Gyáli u. 2-6, H-1097 Budapest, Hungary
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Johnson TJ, Johnson SJ, Nolan LK. Complete DNA sequence of a ColBM plasmid from avian pathogenic Escherichia coli suggests that it evolved from closely related ColV virulence plasmids. J Bacteriol 2006; 188:5975-83. [PMID: 16885466 PMCID: PMC1540072 DOI: 10.1128/jb.00204-06] [Citation(s) in RCA: 130] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Avian pathogenic Escherichia coli (APEC), an extraintestinal pathogenic E. coli causing colibacillosis in birds, is responsible for significant economic losses for the poultry industry. Recently, we reported that the APEC pathotype was characterized by possession of a set of genes contained within a 94-kb cluster linked to a ColV plasmid, pAPEC-O2-ColV. These included sitABCD, genes of the aerobactin operon, hlyF, iss, genes of the salmochelin operon, and the 5' end of cvaB of the ColV operon. However, the results of gene prevalence studies performed among APEC isolates revealed that these traits were not always linked to ColV plasmids. Here, we present the complete sequence of a 174-kb plasmid, pAPEC-O1-ColBM, which contains a putative virulence cluster similar to that of pAPEC-O2-ColV. These two F-type plasmids share remarkable similarity, except that they encode the production of different colicins; pAPEC-O2-ColV contains an intact ColV operon, and pAPEC-O1-ColBM encodes the colicins B and M. Interestingly, remnants of the ColV operon exist in pAPEC-O1-ColBM, hinting that ColBM-type plasmids may have evolved from ColV plasmids. Among APEC isolates, the prevalence of ColBM sequences helps account for the previously observed differences in prevalence between genes of the "conserved" portion of the putative virulence cluster of pAPEC-O2-ColV and those genes within its "variable" portion. These results, in conjunction with Southern blotting and probing of representative ColBM-positive strains, indicate that this "conserved" cluster of putative virulence genes is primarily linked to F-type virulence plasmids among the APEC isolates studied.
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Affiliation(s)
- Timothy J Johnson
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, 1802 Elwood Drive, VMRI 2, Iowa State University, Ames, IA 50011, USA
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Skyberg JA, Johnson TJ, Johnson JR, Clabots C, Logue CM, Nolan LK. Acquisition of avian pathogenic Escherichia coli plasmids by a commensal E. coli isolate enhances its abilities to kill chicken embryos, grow in human urine, and colonize the murine kidney. Infect Immun 2006; 74:6287-92. [PMID: 16954398 PMCID: PMC1695531 DOI: 10.1128/iai.00363-06] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have found an avian pathogenic Escherichia coli (APEC) plasmid, pAPEC-O2-ColV, which contains many of the genes associated with APEC virulence and also shows similarity in content to a plasmid and pathogenicity island of human uropathogenic E. coli (UPEC). To test the possible role of this plasmid in virulence, it was transferred by conjugation along with a large R plasmid, pAPEC-O2-R, into a commensal avian E. coli strain. The transconjugant was compared to recipient strain NC, UPEC strain HE300, and donor strain APEC O2 using various assays, including lethality for chicken embryos, growth in human urine, and ability to cause urinary tract infection in mice. The transconjugant killed significantly more chicken embryos than did the recipient. In human urine, APEC O2 grew at a rate equivalent to that of UPEC strain HE300, and the transconjugant showed significantly increased growth compared to the recipient. The transconjugant also significantly outcompeted the recipient in colonization of the murine kidney. These findings suggest that APEC plasmids, such as pAPEC-O2-ColV, contribute to the pathogenesis of avian colibacillosis. Moreover, since avian E. coli and their plasmids may be transmitted to humans, evaluation of APEC plasmids as possible reservoirs of urovirulence genes for human UPEC may be warranted.
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Affiliation(s)
- Jerod A Skyberg
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
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Johnson TJ, Siek KE, Johnson SJ, Nolan LK. DNA sequence of a ColV plasmid and prevalence of selected plasmid-encoded virulence genes among avian Escherichia coli strains. J Bacteriol 2006; 188:745-58. [PMID: 16385064 PMCID: PMC1347294 DOI: 10.1128/jb.188.2.745-758.2006] [Citation(s) in RCA: 233] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
ColV plasmids have long been associated with the virulence of Escherichia coli, despite the fact that their namesake trait, ColV production, does not appear to contribute to virulence. Such plasmids or their associated sequences appear to be quite common among avian pathogenic E. coli (APEC) and are strongly linked to the virulence of these organisms. In the present study, a 180-kb ColV plasmid was sequenced and analyzed. This plasmid, pAPEC-O2-ColV, possesses a 93-kb region containing several putative virulence traits, including iss, tsh, and four putative iron acquisition and transport systems. The iron acquisition and transport systems include those encoding aerobactin and salmochelin, the sit ABC iron transport system, and a putative iron transport system novel to APEC, eit. In order to determine the prevalence of the virulence-associated genes within this region among avian E. coli strains, 595 APEC and 199 avian commensal E. coli isolates were examined for genes of this region using PCR. Results indicate that genes contained within a portion of this putative virulence region are highly conserved among APEC and that the genes of this region occur significantly more often in APEC than in avian commensal E. coli. The region of pAPEC-O2-ColV containing genes that are highly prevalent among APEC appears to be a distinguishing trait of APEC strains.
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Affiliation(s)
- Timothy J Johnson
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, 1802 Elwood Drive, VMRI #2, Iowa State University, Ames, IA 50011.
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